Condensation product of the benzanthrone series and process of preparing same



Patented May 28, 1929.-

UNITED STATES PATENT- OFFICE.

- GQEORG KRZA NZLEIN AND; MARTIN CORELL, 0F HOGHST-ON-THE-MAIL' I', GERMANY, AS-

SIGNORS TO GRASSEIJLI DYESTUFF CORPORATION,

PORATION OF DELAWARE.

OF NEW YORK, N. Y., A. COR- CQONDENSATION 1 30131101 on THE BENZANTHRONE sEnIns AND ricocnss or rnnrummc SAME.

No Drawing. Application filed March 5, 1926, Serial No. 92,585, and in Germany March 9, 1925.

We have found that by heating a compound of the general formula:

wherein X represents hydrogen or the group 'OCO.C H to a'temperaturebetwecn about 100 C. and about 200 C. in the presence of aluminum chloride while introducing oxygen, new condensation products are obtainable. When using benzoic acid ester of B- naphthol there is obtained whydroxybenzauthrone, whereas when using the dibenzoic acid ester of 2.6-dihydroxynaphthalene the hitherto unknown 1.6-dil1ydroxy-3.4.8.9-dibenzpyrenequinone is obtained.

The following examples serve to illustrate our invention, the parts being'by weight:

1. A mixture of 100 parts of the dibenzoic acid ester of 2.6-dihydroxynaphthalene (melting point 217), 1000 parts of tetrachloroethane and 100 parts of aluminium chloride is heated to boiling for 5 hours while stirring. At the beginning of the reaction the whole becomes dissolved and after a short time the product of the reaction separates.

' This product is drained off, Washed and extracted with boiling water.- The gross yield amounts to 97 parts. The product is then recrystallized from nitrobenzene and has its melting point at 275 C.

Analysis shows that the bodyprobably constitues 1.5-dibenzoyl-2.6-dihydroxynaphthalene:

1 about 140150 2. If the 1.5-dibenzoyl=2.6-dihydroxynaphthalene referred to in Example 1 is melted with ten times the quantity of sodium-aluminium chloride at 140450", while introducing oxygen, the hitherto unknown 1.6dihydroxy-3A.8.Q-dibenzpyrenequinone of the followmg constitution:

in concentrated sulfuric acid to a red solution with a violet hue. It gives with hydrosulfite a red vatdyeing a red tint which, on

exposure to the air, changes to a violet tint which, owing to the presence of the free OH group, does not withstand the action of acid and chlorine. 3. By melting the, benzoic acid ester of ,8

' naphthol with ten times the quantity of soat a temperature of dium-aluminum chloride (1, while introducin oxygen, there is obtained the known a-hy roxybenzanthrone having most probably the formula:

and melting at 176 C.

We claim:

1. As a new product l.6-dihydroxy-3.4.8.9- (libenzpylenequinone of the following constitution:

'chloride' to a temp 2. The process which comprises heating a compound of the general formula:

- wherein X represents hydrogen or the group ).C().C H, in the presence of aluminum chloride to a temperature of from about 100 to about 200 C. while introducing oxygen.

3. The process which comprises heating a compound of the general formula:

wherein represents hydrogen or the group 0.00.0 15 in the presence of aluminum rature of from about "v to about C. while introducing oxygen.

4. The process which comprises heating the dibenzoic acid ester of 2.6-dihydroxy-' hloride to a temperature of from about 140 to about"150 C. while introducing oxygen.

In testimony whereof, weafiix our signatures.

(mono KRANZL IN. MARTIN oonnnnv 

